1. Field of the Invention
The present invention relates to a pouring spout for sparkling beverages, more specifically to an improvement of spout, which is used in a sparkling beverage server or dispenser capable of pouring a sparkling beverage typified by beer under operation of a lever and which can additionally pour, after pouring of a predetermined quantity of the beverage into a vessel such as a mug, fine froth over the beverage in the vessel.
2. Description of the Related Art
Some pouring spouts to be used in apparatuses for pouring sparkling beverages by operating levers, for example, in beer servers, have a function of additionally pouring, after pouring a predetermined quantity of beer into a mug by tilting a lever manually in one direction, fine beer froth over the beer in the mug. As a pouring spout having such a froth adding function, there is disclosed a spout having a frothing function in Japanese Unexamined Patent Publication No. 9-2590. The reason why such fine froth is additionally poured over the beer in a mug is that appropriately frothed beer gives improved texture when the beer goes through ones throat and that the froth prevents carbon dioxide gas from escaping quickly from the beer. Recently, froth to be poured additionally after pouring of beer is required to be as fine as cream.
In a beer server having such a frothing function, a lever attached to a beer pouring spout is switched over to pour beer only or to additionally pour froth from a single nozzle provided in the spout. Therefore, fine froth passes through the nozzle of the beer pouring spout after passage of beer through it, or vice versa. However, it is essential in pouring draft beer from a beer server that there is no residue of beer and froth thereof on the internal surface of the nozzle so as to achieve appropriate frothing of the draft beer poured through it. If beer is poured to another mug with the beer or froth remaining on the internal surface of the nozzle, frothing is likely to occur excessively to give foamy beer. A countermeasure is taken for it by defining an air inlet hole in the pouring nozzle to let the beer and froth remaining on the internal surface of the nozzle drip by their own weights.
As mentioned already, it is true that finely divided creamy foam is required as the additional froth, but creamy froth is highly viscous, so that it is difficult and also takes time to discharge the froth with the aid of air supplied through the air inlet hole. Therefore, it is necessary for an operator, after pouring beer into a mug and carrying out the froth adding operation, to operate the lever in a flash so as to pour liquid beer to flush froth remaining in the spout body and nozzle away from them. However, this operation of flushing the spout body and nozzle with beer inevitably requires a lot of skill, so that there has been awaited an advent of a beer pouring spout capable of pouring constantly fine froth of high quality requiring no such a skill.
Meanwhile, a spout for pouring sparkling beverages is disclosed in Japanese Patent Application No. 2000-19102 filed according to the proposition of the Applicant of the present invention. This spout has a nozzle for pouring a liquid into a mug and another nozzle for pouring froth into the mug, and also contains in its body various kinds of valve mechanisms for opening and closing a liquid channel and a froth channel defined so that a liquid and froth can be poured separately from the respective nozzles.
In the spout for pouring a sparkling beverage described above, the nozzle for pouring froth is long, so that a large amount of froth remains on the internal surface of the nozzle, which is causative of marring the flavor of the liquid. This problem cannot be solved merely by shortening the froth pouring nozzle. If a short froth pouring nozzle is merely used, a vigorous turbulent flow of froth is injected into a mug to be causative of excessive frothing and to be a hindrance in forming fine froth of high quality.
The present inventor has already proposed a countermeasure for the above problem and filed a Japanese Patent Application No. 2001-137771 relating to an invention entitled xe2x80x9cPouring spout for sparkling beverages.xe2x80x9d In the pouring spout according to this invention, a slider is provided in the spout body such that it can slide within a liquid passage defined in its body in intimate contact with the passage under operation of a lever connected to the slider. Meanwhile, a valve seat provided on one end face of the slider is normally urged, by a resilient part attached to the other end face of the slider, to be pressed against the froth pouring valve element and closes the opening of an orifice defined in the froth pouring valve element to communicate with a through hole through which a sparkling beverage passes. When the slider is slid toward the resilient part against the resilience of, the valve seat retracts from the froth pouring valve element to open the opening of the orifice, through which the beverage flows out to impinge against the valve seat and undergoes frothing, and the thus obtained froth is designed to flow to the froth pouring nozzle through an annular groove formed on the internal surface of the spout body.
According to the constitution, the froth formed by impingement of a sparkling beverage against the valve seat is allowed to flow through the annular groove defined in the spout body into the froth pouring nozzle, and thus the impetus of the froth flowing into the nozzle can be attenuated to prevent favorably excessive frothing occurring when a short froth pouring nozzle is used.
However, in the sparkling beverage pouring spout described above, when a liquid or froth thereof is poured, the liquid or froth is brought into contact with the internal surface of the liquid passage defined in the spout body and partly with the slider and remain there. Since the slider repeats sliding in intimate contact with the internal surface of the liquid passage of the spout body under tilting operation of the lever in each time the liquid or froth is poured, the liquid is applied to the internal surface of the liquid passage in the spout body over the full length of the passage and remains there. Thus, the external surface of the slider sliding in intimate contact with the internal surface of the liquid passage defined in the spout body is caused to assume airtightness due to the liquid applied to the passage and remains there.
Meanwhile, if the slider is moved away in a direction such that the valve seat retracts from the froth pouring valve element when froth is to be poured through the sparkling beverage pouring spout, the resilient part retained between the slider and the stopper is pressed against the stopper and is compressed, and the volume of the space in which the stopper and the slider are housed reduces. In this case, due to the high airtightness between the slider and the internal surface of the spout body brought about by the liquid remaining there as described above, the air having been present in that housing space is already ejected along the external surface of the stopper having a lower resistance to airtightness to the outside of the pouring spout. The beer liquid contains a foaming component, so that when the air is ejected along the external surface of the stopper, foaming occurs inevitably accompanied by ejection of the beer liquid. In other words, the ejected beer liquid seeps to the outside of the spout body to deposit thereon, causing contamination of the spout body, disadvantageously.
On the other hand, it is contemplable, as techniques of preventing foaming, in a beer spout structure as disclosed in Japanese Unexamined Patent Publication No. 2000-318799, to notch partly a cover corresponding to the stopper and facilitate incoming and outgoing of air, or to define a through hole in the spout body communicating to the outside. However, these structures are all accompanied by leakage of beer liquid from the spout body to the outside, and wetting of the external surface of the spout body with the seeped beer liquid occurs unavoidably, causing contamination of the external surface.
Meanwhile, Japanese Unexamined Patent Publication No. 2000-318799 discloses a valve mechanism, in which a froth switching valve is contained in a cavity of a first movable rod, and a pressurized beer liquid is allowed to flow into a sliding clearance between the cavity of the first movable rod and a second movable rod by tilting an operation lever clockwise to open the valve. The beer liquid is then injected through orifices defined in an annular U-shaped groove formed on the first movable rod to the external surface of the first movable rod to effect frothing of the beer liquid, and the resulting froth is poured from a froth pouring port through the U-shaped groove. During pouring of froth, the annular U-shaped groove having the orifices for injecting the beer liquid is positioned in alignment with the froth pouring port, and the froth formed through ejection of the beer liquid through the orifices partly forms turbulence and flows down vigorously to the froth pouring port. Therefore, the length of the froth pouring nozzle is increased.
Since the sparkling beverage pouring spout has a long froth pouring nozzle, it involves a problem that a large quantity of froth remains on the internal surface of the nozzle to cause marring of the taste of the beverage. This problem cannot be solved merely by using a short pouring nozzle, but the short froth pouring nozzle injects a vigorous turbulence of froth into a mug, causing excessive frothing or being a factor preventing formation of fine froth of high quality.
Further, the conventional pouring spouts for sparkling beverages involve problems that if the froth remained around the resilient part such as a coiled spring is not discharged but is exposed to the outside air for a long time, it undergoes deterioration, so that the pouring spout must be disassembled and cleaned frequently, taking much trouble, and that the pouring spouts have structures difficult to disassemble.
The present invention was accomplished with a view to solving suitably the problems inherent in the pouring spouts for sparkling beverages of the prior art as described above and is directed to providing a pouring spout for sparkling beverages enabling unskilled operators to carry out appropriate addition of fine and highly viscous froth without requiring the sophisticated skill of cleaning the nozzles and the like with a sparkling beverage nor causing excessive frothing.
Further, the present invention was accomplished with a view to solving suitably the problems inherent in the pouring spouts for sparkling beverages described above and is directed to providing a clean and hygienic pouring spout for sparkling beverages capable of preventing wetting of the spout body with the seeped beverage.
Further, the present invention was accomplished with a view to solving suitably the problems inherent in the pouring spouts for sparkling beverages described above and is directed to providing a pouring spout for sparkling beverages which controls turbulence in pouring froth to prevent excessive frothing and which facilitates disassembling and cleaning.
In order to solve the problems described above and to attain the intended objectives, the pouring spout for a sparkling beverage according to one aspect of the present invention has a constitution in which the sparkling beverage is poured into a vessel by a first operation of a lever, and froth of the sparkling beverage is poured additionally into the vessel by a second operation of the lever; and is characterized in that the pouring spout has a sparkling beverage pouring nozzle and a froth pouring nozzle branching out from a sparkling beverage supply channel defined in a spout body; a slider inserted to the sparkling beverage supply channel to be slidable therein and is connected to the lever to be driven thereby to advance and retract; a sleeve inserted slidably into the sparkling beverage supply channel and is connected at one end to the slider; the sleeve having through holes defined in the peripheral wall to be able to communicate with the froth pouring nozzle at the time of froth pouring operation; a first valve element to be seated on a first valve seat provided at an inlet of the sparkling beverage supply channel under an action of a first resilient part; a valve rod connected at one end to the first valve element and is inserted at the other end to the sleeve; the valve rod having a liquid passage defined axially therein to penetrate the first valve element; and a second valve element inserted to the sleeve and is connected at one end to the valve rod, the second valve element having an orifice defined at the other end to communicate with the liquid passage, that end having the orifice being seated on a second valve seat provided in the slider under an action of a second resilient part; wherein, before operation of the lever, the first valve element is seated on the first valve seat to interrupt flowing of the sparkling beverage into the sparkling beverage supply channel, whereas the second valve is seated on the second valve seat to close the orifice; the first operation of the lever retracts the valve rod in the axial direction against the first resilient part through the second valve element being seated on the second valve seat to let the first valve element leave the first valve seat open and to pour the sparkling beverage out of the sparkling beverage pouring nozzle through the sparkling beverage supply channel; the second operation of the lever causes the slider to advance in the axial direction against the second resilient part to be spaced away from the valve rod forcing the first valve element to seat on the first valve seat, and also causes the second valve element to leave the second valve seat open and effect frothing of the sparkling beverage from the liquid passage when it flows through the orifice to pour the resulting froth from the froth pouring nozzle through the through holes defined in the sleeve.
Here, the sleeve has on the external surface a first annular groove and a second annular groove defined at a necessary interval therebetween, whereas the spout body has a first air vent and a second air vent to allow the sparkling beverage supply channel to communicate with the outside; the sparkling beverage pouring nozzle and the froth pouring nozzle are designed to communicate with the first air vent and the second air vent through the first annular groove and the second annular groove, respectively, only at a fixed position of the sleeve before operation of the lever.
The first operation of the lever interrupts communication between the first annular groove and the first air vent to stop introduction of the outside air into the sparkling beverage pouring nozzle, while communication between the second annular groove and the second air vent is maintained to introduce outside air still into the froth pouring nozzle. Meanwhile, the second operation of the lever interrupts communication between the second annular groove and the second air vent to stop introduction of the outside air into the froth pouring nozzle, while communication between the first annular groove and the first air vent is maintained to introduce outside air still into the sparkling beverage pouring nozzle.
In order to solve the problems described above and to attain the intended objectives, the pouring spout for a sparkling beverage according to another aspect of the present is provided with a slider sliding within a liquid passage defined in a spout body in intimate contact therewith; a lever connected to the slider and is tilted to slide the slider within the liquid passage; a resilient part disposed on one end face of the slider so as to press a valve seat provided on the other end face of the slider against a pouring valve element disposed to oppose the latter end face; a through hole for the sparkling beverage defined in the inside of the pouring valve element and opens to that end face against which the valve seat for the pouring valve element is pressed; a pouring nozzle providing a channel of the sparkling beverage flowed out from an opening of the through hole opened by retraction of the valve seat from the pouring valve element when the slider is slid toward the other end face against the resilience of the resilient part; and a communicating passage for securing communication between a housing space defined in the spout body, in which the resilient part is housed and the pouring nozzle.
In order to solve the problems described above and to attain the intended objectives, the pouring spout for a sparkling beverage according to another aspect of the present invention is provided with a slider sliding within a liquid passage defined in a spout body in intimate contact therewith; a lever connected to the slider and is to be tilted to slide the slider within the liquid passage; a resilient part disposed on one end face of the slider so as to press a valve seat provided on the other end face of the slider against a froth pouring valve element disposed to oppose the latter end face; an orifice defined as a passage for the sparkling beverage introduced into the froth pouring valve element and opening to the froth pouring valve element; an annular groove defined on the internal surface of the spout body such that it provides a channel for froth formed when the sparkling beverage flowed out through the opening opened by retraction of the valve seat from the froth pouring valve element by sliding the slider toward that former end face against the resilience of the resilient part impinge against the valve seat; and a froth pouring nozzle communicating with the annular groove.
Other aspects and advantages of the invention will become apparent from the following description, taken in conjunction with the accompanying drawings illustrated by way of examples the principles of the invention.